<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>绝对定位的深入探索-span</title>
    <style>
        span{
            width: 100px;
            height: 100px;
            background: yellow;
            position: absolute;
            /* position: relative;无效 */
        }
        /* 
        1.display：block;
        2.position：absolute;
        3.float:left;
        */
    </style>
</head>
<body>
    <span>hello</span>
</body>
</html>